1. Field of the Invention
The present invention relates to the field of communications. More particularly, the present invention relates to dynamically establishing broadband quality of service (QoS) connections, on demand, between peers on a network to guarantee application specific IP QoS via the combination of ATM switched virtual connections (SVCs) and permanent virtual connection (PVCs). Alternative processes are disclosed, including (i) dynamically establishing an SVC shortcut connection from a peer device using an SVC signaling proxy device without going through an ISP, and (ii) creating multiple virtual user-to-network interfaces (UNIs) within a single virtual path (VP) at each port of an ATM edge switch to establish SVCs between subscribers.
2. Background Information
Network carriers are currently providing broadband access services to a large number of subscribers using asynchronous transfer mode (ATM) and digital subscriber lines (DSL). Under the current paradigm, subscribers connect to an Internet service provider (ISP) using a pre-existing static point-to-point or “nailed up” connection, e.g., a PVC. Once the connection has been established the subscriber can communicate to the ISP, via the connection, using various bridge or router modes. In the case of bridge mode, typically point-to-point protocol (PPP) or point-to-point protocol over Ethernet (PPPoE) is used to set up the user sessions and carry the user IP packets to the ISP. When a subscriber wishes to communicate with a peer subscriber, all communications via IP packets travel through the ISP, thus suffering implementation complexity and operational unfeasibility for supporting application specific QoS.
Furthermore, subscribers currently interface with the ATM network over PVCs via standard UNIs. To support on-demand, SVC-based connections, each customer must be able to dynamically signal connection establishment requests to the ATM network. If both ATU-R and ATM switch support SVC, but the DSLAM does not, the current virtual UNI-based implementations suffer from scalability limitations. For example, using a single UNI supports only a single customer because one signaling channel exists for the entire UNI. Using virtual UNIs expands the limit to 256 customers because virtual UN's sub-divide the UNI into a maximum of 256 virtual UNIs, each having a unique Virtual Path Identifier (VPI). However, a single virtual UNI, which supports ATM network access of a single subscriber, requires an entire VP, even though most of the virtual channels (VCs) within the VP are not needed to support the SVC. A limited number of VPs are available at each port of an ATM edge switch and/or a digital subscriber line access multiplexer (DSLAM) connected to the ATM edge switch, which accordingly restricts the number of UNIs that may be supported by the network at any one time. For example, a DS3 or a OC3 port typically accommodates at most 256 VPIs, thereby limiting each port to support of 256 virtual UNIs, even though a DSLAM may service thousands of subscribers.
It is desirable to have a system that enables each VP to support multiple UNIs, expanding the ATM network's capability to support guaranteed QoS connections, without having to increase the number of physical ports of various network elements.